



1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 1, 4, 4, 4, 4, 1, 2, 2, 1, 2, 2, 1, 2, 1, 2, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 2, 1, 2, 2, 1, 2, 2, 1, 4, 2, 4, 2, 1, 2, 4, 2, 4, 1, 1, 2, 2, 1, 2, 2, 1, 2, 2, 1, 1, 2, 2, 1, 2, 2, 1, 2, 2, 1, 2, 2
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OFFSET

1,5


COMMENTS

For Lucas sequences, say, rows in A172236, we are mainly concerned about the periods, ranks and the ratios of the periods to the ranks of them modulo a given integer n. The period of {A172236(k,m) modulo m} is given as A321477(n,k), and the rank, which is defined as the smallest l > 0 such that n divides A172236(k,l), is given as A321476(n,k). T(n,k) is their ratio, which is the multiplicative order of A172236(k,A321476(n,k)+1) modulo n.
T(n,k) has value 1, 2 or 4. This is because A172236(k,m+1)^4 == 1 (mod A172236(k,m)). For n > 2, T(n,k) = 4 iff A321476(n,k) is odd; 1 iff A321476(n,k) is even but not divisible by 4; 2 iff A321476(n,k) is divisible by 4. See A172236 for some further properties.
Let p be an odd prime. If p == 3 (mod 4), the p^eth row consists of only 1 and 2; if p == 5 (mod 8), the p^eth row consists of only 1 and 4.


LINKS

Table of n, a(n) for n=1..78.


EXAMPLE

Table begins
1,
1, 1,
1, 2, 2,
1, 1, 1, 1,
1, 4, 4, 4, 4,
1, 2, 2, 1, 2, 2,
1, 2, 1, 2, 2, 1, 2,
1, 2, 1, 2, 1, 2, 1, 2,
1, 2, 2, 1, 2, 2, 1, 2, 2,
1, 4, 2, 4, 2, 1, 2, 4, 2, 4,
...


PROG

(PARI) A172236(k, m) = ([k, 1; 1, 0]^m)[2, 1]
T(n, k) = my(i=1); while(A172236(k, i)%n!=0, i++); znorder(Mod(A172236(k, i+1), n))


CROSSREFS

Cf. A172236, A321476, A321477.
Sequence in context: A228528 A219244 A330231 * A273638 A277582 A037803
Adjacent sequences: A323014 A323015 A323016 * A323018 A323019 A323020


KEYWORD

nonn,tabl


AUTHOR

Jianing Song, Jan 07 2019


STATUS

approved



